The billionaire hedge-fund investor Steven A. Cohen likes to keep his shopping sprees to himself. But that's pretty difficult in today's gossipy art world, especially when he recently spent more than $100 million on two well-documented paintings, one by Vincent van Gogh and the other by Paul Gauguin.

When the seller is another high-profile collector - the Las Vegas casino owner Stephen A. Wynn - the transaction becomes all the more fascinating.

The paintings are van Gogh's "Peasant Woman Against a Background of Wheat" (1890) and Gauguin's "Bathers" (1902), and they once hung in the Bellagio Gallery of Fine Art in Las Vegas, which was founded by Mr. Wynn, and were included in a 1999 catalog of the gallery's holdings. (When Mr. Wynn sold Mirage Resorts to MGM Grand in 2000, MGM transformed the gallery from a place to show Mr. Wynn's art collection to a kunsthalle, a museum without its own collection that presents loan exhibitions.)

The sale of the van Gogh and the Gauguin was brokered by William Acquavella, the Manhattan dealer who has advised Mr. Cohen and Mr. Wynn over the years.

Mr. Cohen would not discuss the transaction. Mr. Wynn did not return repeated phone calls. Mr. Acquavella declined to comment.

Ed Tagliaferri, a spokesman for Mr. Cohen, at first said he would not comment, but then said that the $150 million figure Mr. Cohen was rumored to have paid for the two paintings was too high. (People familiar with the negotiations said that they believed the correct amount was around $110 million.)

The Gauguin, one of that artist's signature Tahitian images, is a colorful canvas that depicts a family of bathers in a lush landscape with the ocean in the background. Mr. Wynn bought the painting in the late 1990's. It had previously belonged to a member of the Goulandris family, Greek shippers known for their serious collecting. The van Gogh, a seated woman wearing a blue dress and straw hat and surrounded by stalks of wheat, was also bought by Mr. Wynn in the 1990's. Before his purchase it had had several owners, including the Hahnloser Collection from Switzerland. Like many collectors, Mr. Wynn is both a steady buyer and a steady seller. He has parted with works by Modigliani and Cézanne, for example, at auction and in private sales.

Mr. Cohen has sold his share of paintings, too. Two years ago he auctioned a Cézanne still life at Sotheby's. But to the dealers who as a professional pastime watch Mr. Cohen's transactions, his sales have not been as surprising as this latest round of purchases.

During the last five years he has spent more than $400 million on art. He has snapped up postwar canvases, like a classic Jackson Pollock drip painting for $52 million, Andy Warhol's "Superman" for $25 million and an early painting by Francis Bacon for $16.5 million. He has also bought newer art, like Damien Hirst's 1991 work "The Physical Impossibility of Death in the Mind of Someone Living," a 14-foot tiger shark in a tank of formaldehyde, for which he paid $8 million.

Most recently he has concentrated on contemporary art, collecting other pieces by Mr. Hirst as well as prime examples of work by such trendy living artists as Richard Prince and Tom Friedman.

So why is he suddenly buying a van Gogh and a Gauguin?

When Mr. Cohen began seriously collecting, he purchased several important Impressionist and post-Impressionist paintings, including one of Monet's "Waterlilies" from 1906 and a Manet self-portrait from 1878. Some dealers say he is once again looking back in time. They suggest that Mr. Cohen, ever the trader, may believe the contemporary market has become too overheated.

Others dealers (particularly those who specialize in cutting-edge contemporary art) disagree, arguing that he is not abandoning one market for another but participating in both. None would speak for attribution, because of Mr. Cohen's importance as a client.

A Double Dose of Sculpture

The art program at Madison Square Park - that newly restored 6.2-acre swath of green space between Madison and Fifth Avenues from 23rd to 26th Streets - keeps growing. It began slowly, four years ago, with a video installation by Tony Oursler. Now there are plans to show art there year-round.

And not just one artist at a time. On Oct. 21, 11 works by the minimalist sculptor Jene Highstein will join the two monumental sculptures by Sol LeWitt that were installed May 1.

"This show marks a big step forward for us," said Debbie Landau, executive director of the Madison Square Park Conservancy, a two-year-old group made up of neighborhood residents and business leaders. "We're using the lawn and the planting beds as though they were rooms in a museum."

Mr. Highstein's installation will consist of sculptures from 1988 to 2004 and made of cast iron, stone and wood. "I've been messing around in the space for the last three months," Mr. Highstein said in a telephone interview on Wednesday. "I'm used to putting works in the landscape, but mostly site-specific pieces."

Mr. Highstein said that out of respect for Mr. LeWitt, whose works do not address the landscape, he arranged his sculptures so that they circle the park from the northeast corner to the southwest corner, keeping the central lawn empty as a buffer between the two groupings.

He placed two sculptures fashioned from Western red cedar, for example, in the northern end of the park. "I didn't want them to compete with the trees," Mr. Highstein said. "But they're quite architectural and play off the big oak trees there."

The older, cast iron works - low cylindrical forms with slanting tops in smooth and textured black granite - are in the park's southwestern triangle. Three of Mr. Highstein's "Tornado" pieces, funnel-shaped forms in quartzite, are just north of the cast-iron works.

New at the New Museum

On Tuesday the 28-year-old New Museum of Contemporary Art will break ground for its $35 million building at the Bowery and Prince Street. The 60,000-square-foot, seven-story museum was designed by Kazuyo Sejima and Ryue Nishizawa, in partnership as Sanaa of Tokyo.

When the building opens in late 2007, the museum will have a larger curatorial staff. In June, Lisa Phillips, the museum's director, hired Richard Flood, chief curator of the Walker Art Center in Minneapolis, to be its chief curator. This week she announced the appointment of Laura Hoptman as a curator.

Ms. Hoptman was most recently curator of contemporary art at the Carnegie Museum of Art in Pittsburgh, where she organized the 2004-5 Carnegie International. Earlier, she was an assistant curator of drawings at the Museum of Modern Art.

Rosenquist at Acquavella

Although William Acquavella has built his reputation by dealing in Impressionist and post-Impressionist art, his East 79th Street gallery in Manhattan also represents living artists, including Lucian Freud.

Now the Pop artist James Rosenquist has agreed to be represented by Mr. Acquavella. In his long career, Mr. Rosenquist had been represented by such high profile dealers as Leo Castelli and Larry Gagosian.

A show of his grisaille and monochrome works opened at Acquavella Galleries this week and continues through Nov. 11.